/*
* \brief Internet protocol version 4.
* \author Stefan Kalkowski
* \date 2010-08-19
*/
/*
* Copyright (C) 2010-2017 Genode Labs GmbH
*
* This file is part of the Genode OS framework, which is distributed
* under the terms of the GNU Affero General Public License version 3.
*/
#ifndef _IPV4_H_
#define _IPV4_H_
/* Genode */
#include
#include
#include
#include
#include
#include
#include
#include
namespace Genode { class Output; }
namespace Net {
enum { IPV4_ADDR_LEN = 4 };
class Ipv4_address;
class Ipv4_packet;
static inline Genode::size_t ascii_to(char const *, Net::Ipv4_address &);
}
struct Net::Ipv4_address : Network_address
{
Ipv4_address(Genode::uint8_t value = 0) : Network_address(value) { }
Ipv4_address(void *src) : Network_address(src) { }
bool valid() const { return *this != Ipv4_address(); }
Genode::uint32_t to_uint32_big_endian() const;
static Ipv4_address from_uint32_big_endian(Genode::uint32_t ip_raw);
Genode::uint32_t to_uint32_little_endian() const;
static Ipv4_address from_uint32_little_endian(Genode::uint32_t ip_raw);
bool is_in_range(Ipv4_address const &first,
Ipv4_address const &last) const;
}
__attribute__((packed));
/**
* Data layout of this class conforms to an IPv4 packet (RFC 791)
*
* IPv4-header-format:
*
* ----------------------------------------------------------------
* | 0-3 | 4-7 | 8-11 | 12-15 | 16-18 | 19-23 | 24-27 | 28-31 |
* ----------------------------------------------------------------
* | version | IHL | service-type | total-length |
* ----------------------------------------------------------------
* | identifikation | flags | fragment-offset |
* ----------------------------------------------------------------
* | ttl | protocol | header-checksum |
* ----------------------------------------------------------------
* | source-ip-address |
* ----------------------------------------------------------------
* | destination-ip-address |
* ----------------------------------------------------------------
* | options ... |
* ----------------------------------------------------------------
*/
class Net::Ipv4_packet
{
public:
enum Size {
ADDR_LEN = IPV4_ADDR_LEN, /* Ip address length in bytes */
};
static Ipv4_address current() { return Ipv4_address((Genode::uint8_t)0x00); }
static Ipv4_address broadcast() { return Ipv4_address((Genode::uint8_t)0xff); }
static Ipv4_address ip_from_string(const char *ip);
void update_checksum();
bool checksum_error() const;
private:
/************************
** IPv4 header fields **
************************/
struct Offset_6_u16 : Genode::Register<16>
{
struct Fragment_offset : Bitfield<0, 13> { };
struct Flags : Bitfield<13, 3> { };
struct More_fragments : Bitfield<13, 1> { };
struct Dont_fragment : Bitfield<14, 1> { };
};
struct Offset_0_u8 : Genode::Register<8>
{
struct Ihl : Bitfield<0, 4> { }; /* Internet Header Length */
struct Version : Bitfield<4, 4> { };
};
struct Offset_1_u8 : Genode::Register<8>
{
struct Ecn : Bitfield<0, 2> { }; /* Explicit Congestion Notification */
struct Dscp : Bitfield<2, 6> { }; /* Differentiated Services Code Point */
};
Genode::uint8_t _offset_0_u8;
Genode::uint8_t _offset_1_u8;
Genode::uint16_t _total_length;
Genode::uint16_t _identification;
Genode::uint16_t _offset_6_u16;
Genode::uint8_t _time_to_live;
Genode::uint8_t _protocol;
Genode::uint16_t _checksum;
Genode::uint8_t _src[ADDR_LEN];
Genode::uint8_t _dst[ADDR_LEN];
unsigned _data[0];
public:
enum class Protocol : Genode::uint8_t
{
ICMP = 1,
TCP = 6,
UDP = 17,
};
template
T const &data(Size_guard &size_guard) const
{
size_guard.consume_head(sizeof(T));
return *(T const *)(_data);
}
template
T &data(Size_guard &size_guard)
{
size_guard.consume_head(sizeof(T));
return *(T *)(_data);
}
template
T &construct_at_data(SIZE_GUARD &size_guard)
{
size_guard.consume_head(sizeof(T));
return *Genode::construct_at(_data);
}
Genode::size_t size(Genode::size_t max_size) const;
/***************
** Accessors **
***************/
Genode::size_t header_length() const { return Offset_0_u8::Ihl::get(_offset_0_u8); }
Genode::uint8_t version() const { return Offset_0_u8::Version::get(_offset_0_u8); }
Genode::uint8_t diff_service() const { return Offset_1_u8::Dscp::get(_offset_1_u8); }
Genode::uint8_t ecn() const { return Offset_1_u8::Ecn::get(_offset_1_u8); }
Genode::size_t total_length() const { return host_to_big_endian(_total_length); }
Genode::uint16_t identification() const { return host_to_big_endian(_identification); }
Genode::uint8_t flags() const { return (Genode::uint8_t)Offset_6_u16::Flags::get(host_to_big_endian(_offset_6_u16)); }
bool dont_fragment() const { return Offset_6_u16::Dont_fragment::get(host_to_big_endian(_offset_6_u16)); }
bool more_fragments() const { return Offset_6_u16::More_fragments::get(host_to_big_endian(_offset_6_u16)); }
Genode::size_t fragment_offset() const { return Offset_6_u16::Fragment_offset::get(host_to_big_endian(_offset_6_u16)); }
Genode::uint8_t time_to_live() const { return _time_to_live; }
Protocol protocol() const { return (Protocol)_protocol; }
Genode::uint16_t checksum() const { return host_to_big_endian(_checksum); }
Ipv4_address src() const { return Ipv4_address((void *)&_src); }
Ipv4_address dst() const { return Ipv4_address((void *)&_dst); }
void header_length(Genode::size_t v) { Offset_0_u8::Ihl::set(_offset_0_u8, v); }
void version(Genode::uint8_t v) { Offset_0_u8::Version::set(_offset_0_u8, v); }
void diff_service(Genode::uint8_t v) { Offset_1_u8::Dscp::set(_offset_1_u8, v); }
void ecn(Genode::uint8_t v) { Offset_1_u8::Ecn::set(_offset_1_u8, v); }
void total_length(Genode::size_t v) { _total_length = host_to_big_endian((Genode::uint16_t)v); }
void identification(Genode::uint16_t v) { _identification = host_to_big_endian(v); }
void time_to_live(Genode::uint8_t v) { _time_to_live = v; }
void protocol(Protocol v) { _protocol = (Genode::uint8_t)v; }
void checksum(Genode::uint16_t checksum) { _checksum = host_to_big_endian(checksum); }
void src(Ipv4_address v) { v.copy(&_src); }
void dst(Ipv4_address v) { v.copy(&_dst); }
void flags(Genode::uint8_t v)
{
Genode::uint16_t be = host_to_big_endian(_offset_6_u16);
Offset_6_u16::Flags::set(be, v);
_offset_6_u16 = host_to_big_endian(be);
}
void fragment_offset(Genode::size_t v)
{
Genode::uint16_t be = host_to_big_endian(_offset_6_u16);
Offset_6_u16::Fragment_offset::set(be, v);
_offset_6_u16 = host_to_big_endian(be);
}
void dont_fragment(bool v)
{
Genode::uint16_t be = host_to_big_endian(_offset_6_u16);
Offset_6_u16::Dont_fragment::set(be, v);
_offset_6_u16 = host_to_big_endian(be);
}
void more_fragments(bool v)
{
Genode::uint16_t be = host_to_big_endian(_offset_6_u16);
Offset_6_u16::More_fragments::set(be, v);
_offset_6_u16 = host_to_big_endian(be);
}
/*********
** log **
*********/
void print(Genode::Output &output) const;
} __attribute__((packed));
Genode::size_t Net::ascii_to(char const *s, Net::Ipv4_address &result)
{
using namespace Genode;
Net::Ipv4_address buf;
size_t number_idx = 0;
size_t read_len = 0;
while (1) {
/* read the current number, fail if there's no number */
size_t number_len = ascii_to_unsigned(s, buf.addr[number_idx], 10);
if (!number_len) {
return 0; }
/* update read length and number index */
read_len += number_len;
number_idx++;
/* if we have all numbers, fill result and return read length */
if (number_idx == sizeof(buf.addr) / sizeof(buf.addr[0])) {
result = buf;
return read_len;
}
/* as it was not the last number, check for the following dot */
s += number_len;
if (*s != '.') {
return 0; }
read_len++;
s++;
}
}
#endif /* _IPV4_H_ */